[llvm-commits] [llvm] r165187 - in /llvm/trunk: lib/Transforms/Scalar/IndVarSimplify.cpp test/Transforms/IndVarSimplify/crash.ll

[Andrew Trick]

On Oct 4, 2012, at 12:19 AM, Eric Christopher <echristo at gmail.com> wrote:

>> 
>>   // Do LFTR if the exit condition's IV is *not* a simple counter.
>> -  Value *IncV = Phi->getIncomingValueForBlock(L->getLoopLatch());
>> +  int Idx = Phi->getBasicBlockIndex(L->getLoopLatch());
>> +  if (Idx < 0)
>> +    return true;
>> +  Value *IncV = Phi->getIncomingValue(Idx);
>>   return Phi != getLoopPhiForCounter(IncV, L, DT);
>> }
>> 
>> 
> 
> Please update the comment to correspond to the change in behavior.

Kuba,

I was ok with your patch (thanks!), but if you plan to cleanup/comment, then consider whether it would be more self-documenting to do this instead:

+PHINode *Phi = dyn_cast<PHINode>(LHS);
+ if (!Phi || Phi->getParent() != L->getHeader())
+  Phi = getLoopPhiForCounter(LHS, L, DT);

-Andy